1. Field of the Invention
The invention is directed to a suspension strut including a cylinder and a vertically adjustable spring perch having a sleeve portion which is connected to the cylinder.
2. Description of the Related Art
DE 85 10 058 U1 discloses a suspension strut with a removable spring perch which is supported in a holder ring. The holder ring can be fastened to the cylinder of the suspension strut independent from the spring perch and coated as a component unit. The vertical adjustment of the spring perch is determined by the holder ring and can not be altered.
DE 198 51 019 C1 discloses a suspension strut whose cylinder has a holding ring for a fixedly adjustable spring perch. At least one groove is shaped into the holding ring, wherein a circumferential area of a sleeve portion of the spring perch can be deformed radially in this groove. The overlapping of the sleeve portion with the groove defines the maximum vertical adjustment of the spring perch.
Further, a spring unit for motor vehicles is known from DE 197 44 757 A1, wherein the height position of a spring perch is actively adjustable through the use of a hydraulic medium. A spring unit of this kind is provided particularly for raised vehicles in which it is necessary to adjust the spring perch frequently in connection with a height control of the vehicle body.
It is the object of the present invention to provide a suspension strut with a vertically adjustable spring perch, particularly relating to lasting vertical adjustment.
According to the invention, a chamber is arranged on the cylinder side which is at least partly filled with a moldable material, the sleeve portion contacts the moldable material, which transmits a supporting force from the cylinder to the spring perch in the solid state.
Both plastic and metallic materials can be used as moldable material. During vertical adjustment, the spring perch is held in its predetermined position and the chamber is filled with an appropriate amount of moldable material.
For this purpose, the cylinder-side chamber can be formed by a supporting ring which is axially fixedly connected to the cylinder.
In another advantageous construction, the supporting ring has a sleeve and a base and the sleeve portion is held at least partly within the sleeve of the supporting ring. In this variant, the supporting ring forms the chamber for the moldable material.
With regard to good accessibility for a corresponding device, the supporting ring has a connection opening for the moldable material.
In case of special installation space conditions, it may be necessary that the supporting ring has only a very small outer diameter. For such cases, the supporting ring determines the chamber for the moldable material with a mold sleeve of a device. After the material is fed into the chamber, the mold sleeve can be removed.
When a supporting ring with very simple geometry is required, the sleeve portion of the spring perch can be constructed in such a way that it surrounds the supporting ring radially. In the simplest case, the supporting ring can be formed by a disk.
In an advantageous further development, the sleeve portion has deformations which are oriented radially inward. These deformations serve to improve the axial connection between the moldable material and the sleeve portion, but offer the additional advantage that a safety stop is achieved for the spring perch with suitable dimensioning of the deformations in relation to the outer diameter of the supporting ring.
In a constructional variant, the chamber is formed at least partly by a radial shaped portion of the cylinder. Depending on the available shaping devices, a radial inner or radial outer shaped portion of the cylinder can be provided. Finally, the partial difference between a nominal diameter and the shaped portion diameter is used determine a chamber.
Depending on the selected material, it can be useful for the sleeve portion to have a radial outward shaped wall area which defines the chamber. This variant is usable particularly with metallic moldable material.
Further, a safety stop can be arranged on the cylinder side for the spring perch.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.